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Psychology in the Schools, Vol. 46(2), 2009 C© 2008 Wiley Periodicals, Inc.Published online in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/pits.20358

PEER VICTIMIZATION IN CHILDREN WITH ATTENTION-DEFICIT/HYPERACTIVITYDISORDER

JUDITH WIENER

Department of Human Development and Applied Psychology, Ontario Institute for Studies in Education,University of Toronto

MEGHAN MAK

Psychology Department, Mount Royal College

This study explored peer victimization in 9- to 14-year-old children with and without Attention-Deficit/Hyperactivity Disorder (ADHD). The sample comprised 104 children, 52 of whom hada previous ADHD diagnosis. Children with ADHD had higher overall rates of self-reported vic-timization by peers and parent- and teacher-reported bullying behavior than did children withoutADHD. The rates of victimization were especially high for girls with ADHD. Furthermore, chil-dren with ADHD reported higher frequencies of verbal, physical, and relational victimization thandid children without ADHD. When data were pooled from children, parents, and teachers, chil-dren with ADHD were categorized as victims, bullies, and bully/victims significantly more oftenthan were children without ADHD. Parent ratings of ADHD symptoms predicted self-reportedvictimization by peers. Neither parent-rated anxious-shy behaviors nor parent- and teacher-ratedsocial skills predicted victimization by peers over and above ADHD symptoms. Parent ratingsof oppositional behavior mediated the relationship between ADHD symptoms and parent- andteacher-rated bullying. C© 2008 Wiley Periodicals, Inc.

This study is an investigation of peer victimization in 9- to 14-year-old children with andwithout Attention-Deficit/Hyperactivity Disorder (ADHD). Peer victimization occurs when one ormore children perform negative actions toward another child repeatedly and over time (Olweus,1993). These negative behaviors entail physical, verbal, or relational aggression, and involve animbalance of power. Bullies are the perpetrators of these negative actions; victims are the targets ofbullies and cannot defend themselves adequately (Crick, 1995).

Children who are chronically victimized by peers or who bully others are at risk for serious ad-justment problems. Chronic victimization by peers increases risk for anxiety, loneliness, depression,social withdrawal, low self-esteem, suicidal tendencies, dislike and avoidance of school, and pooracademic performance (Boivin, Hymel, & Bukowski, 1995; Olweus, 1991; Perry, Hodges, & Egan,2001). Victimization contributes to later social adjustment problems such as friendlessness and peerrejection (Ladd, Kochenderfer, & Coleman, 1997). Bullies are often impulsive, frequently exhibitantisocial behavior, and are at increased risk for maladaptive outcomes such as criminal behavior(Olweus, 1995). Children who are bullies more often display characteristics of conduct disorder,oppositional defiant disorder, and ADHD than do children who are not bullies (Coolidge, DenBoer,& Segal, 2002; Salmon, James, Cassidy, & Javaloyes, 2000). Some children fit the profile of bothvictims and bullies and are referred to as provocative victims or bully/victims (Olweus, 1978). Thesechildren tend to display the anxiety, depression, and low self-esteem seen in victims, concurrent withthe high levels of dominance, aggression, and antisocial behavior typical of bullies (Olweus, 2001).They often provoke bullying through their aggressive behavior, but are unable to defend themselvesadequately (Olweus, 1993). Bully/victims appear to be at higher risk for maladjustment and rejectionby their peers than do children who are solely victimized or who solely bully others (Schwartz, 2000).

Despite the negative outcomes associated with peer victimization, there is a paucity of researchwith samples of children with diagnosed ADHD. Consequently, the present study was guided

Correspondence to: Dr. Judith Wiener, Department of Human Development and Applied Psychology, OISE/University of Toronto, 252 Bloor Street West, Toronto, Ontario, M5S IV6, Canada. E-mail: [email protected]

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ADHD Peer Victimization 117

by two objectives: 1) to determine whether 9- to 14-year-old children with and without ADHDdiffer in frequency of self-reported victimization by peers and self-, parent-, and teacher-reportedbullying; and 2) to determine whether factors that predict peer victimization in typically developingchildren account for significant portions of the variance in peer victimization over and above ADHDsymptoms. The specific factors that were explored were anxious and shy behavior, social skills, andoppositional behavior.

Frequency of Peer Victimization

Although children with ADHD often have associated aggression, anxiety, and depression(American Psychiatric Association, 1994), are frequently rejected by their peers (e.g., Bagwell,Molina, Pelham, & Hoza, 2001; Gresham & MacMillan, 1997; Gresham, MacMillan, Bocian, Ward,& Forness, 1998; Hinshaw, 2002), are intrusive, inappropriate, disorganized, aggressive, impulsive,emotional, uncooperative, and bossy in their peer relationships (see Stormont, 2001, for a review),and have a behavioral profile similar to children who are both bullies and victims (i.e., problems withconcentration, hyperactivity, and impulsivity) (Barkley, 2006; Kumpulainen et al., 1998; Olweus,2001), frequency of peer victimization in this population has only been explicitly investigated in oneprevious study. Unnever and Cornell (2003) found that children classified as having ADHD on thebasis of self-reports of taking stimulant medication were at increased risk for being victimized bypeers and for being perpetrators of bullying when compared to their classmates.

The results of this study raise several questions. First, as indicated by Unnever and Cornell(2003), studies should be carried out with children with ADHD where a diagnosis can be confirmed.Second, the proportion of children with ADHD who had peer victimization problems was not clear.In school-based studies using self-report measures, classification as bully, victim, or bully/victimvaries depending on the cutoff score used. The ranges in studies using various modified versions ofa questionnaire developed by Olweus (1991, 1993) with similar cutoffs to the present study were11%–11.4% for victims, 9%–14% for bullies, and 2%–5% for bully/victims (Pellegrini, Bartini, &Brooks, 1999; Rigby, 1994, 1998).

Third, peer victimization is often described based on the type of aggression it involves. Physicalvictimization includes such actions as hitting, kicking, punching or tripping. Verbal victimizationincludes threats of physical harm, name-calling, teasing, or general verbal harassment. Relationalvictimization includes gossip, exclusion from a group, or threatening the withdrawal of a friendshipor group acceptance (Crick, 1995). There are no published studies that investigated the relativefrequency of verbal, relational, and physical victimization in children with ADHD. In a qualitativestudy, however, Shea and Wiener (2003) found that social exclusion was the most salient form ofvictimization by peers for four chronically victimized boys with ADHD.

Fourth, it is not clear whether there are gender differences in peer victimization in children withADHD. Unnever and Cornell (2003) did not find gender differences, and the participants in the Sheaand Wiener (2003) study were all boys. Gaub and Carlson’s (1997) meta-analysis showed no genderdifferences in peer acceptance and rejection. Berry, Shaywitz, and Shaywitz (1985), however, foundthat both preschool and school-age girls with ADHD were more at risk for being rejected by peersthan were boys with ADHD, and Rucklidge and Tannock (2001) found that parents and teachers ratedfemale adolescents with ADHD as having more social problems than their male counterparts. Perryet al. (2001) and Espelage, Mebane, and Swearer (2004) reviewed the substantial literature on genderdifferences in peer victimization and bullying. Both reviews indicated that boys and girls are equallylikely to be victims of bullying, and that gender differences are entangled with developmental effectsand type of aggression. Boys are more likely to engage in and be subject to physical aggression bypeers, whereas girls typically perpetrate or are victims of relational aggression. Boys and girls do not

Psychology in the Schools DOI: 10.1002/pits

118 Judith Wiener and Meghan Mak

differ in the frequency of being targets of verbal aggression (Kochenderfer & Ladd, 1997). Althoughpeer victimization is frequent in the older elementary school grades, it is generally highest inmiddle school (National Center for Educational Statistics, 1995). Girls tend to progress more rapidlythan boys in terms of the kind of bullying in which they are involved (Craig, Pepler, Connolly,& Henderson, 2001). Tremblay et al. (1995), for example, found that girls’ physical aggressiondecreases and relational aggression increases at an earlier age than boys’.

The fifth question pertains to measurement of peer victimization. Although trained observersand peers typically provide reliable and valid indicators (Juvonen, Nishina, & Graham, 2001;Pellegrini, 2001), it is not practical to do observational or sociometric studies if each participantattends a different school, as is typical of a clinically referred sample. Self-reports, parent reports,and teacher reports are more practical, but have some limitations. Children with ADHD, whomay have a hostile attribution bias (e.g., Milich & Dodge, 1984), may attribute gentle teasingor accidental physical altercation as intentional and malicious, and thus may overreport beingvictimized. Nevertheless, much of the victimization may not be observable by parents and teachers(Craig & Pepler, 1997; Pellegrini, 2001), who also may not be aware of victimized children’spsychological distress (Schwartz, McFayden-Ketchum, Dodge, Pettit, & Bates, 1998). Most childrentend to be reluctant to report that they are perpetrators of bullying (Pellegrini, 2001; Pellegrini &Bartini, 2000). Failure to report being a perpetrator of bullying may be especially problematic forchildren with ADHD who have been found to have a positive illusory bias (e.g., Hoza, Pelham,Milich, Pillow, & McBride, 1993; Hoza, Pelham, Dobbs, Owens, & Pillow, 2002).1 Therefore,teacher-, parent-, and self-reports were used in the present study to assess bullying, and self-reportwas used to assess victimization by peers.

This study tested three hypotheses that pertain to frequency of peer victimization in childrenwith ADHD. 1) Children with ADHD will report higher levels of victimization by peers than willchildren without ADHD. We will explore whether the hypothesized higher levels of victimization bypeers include verbal, relational, and physical victimization and whether there are gender differencesin frequency of victimization. 2) Parents and teachers will report that children with ADHD bully andthreaten others more often than children without ADHD. It is unclear, however, whether self-reportsof bullying of children with and without ADHD would differ. We will also explore whether thereare gender differences in frequency of bullying. 3) Using a multisource (i.e., self-, parent-, andteacher-report) method of classification, children with ADHD will be categorized as victims, bullies,and bully/victims more often than comparison children.

Predictors of Peer Victimization

The social-ecological perspective on peer victimization suggests that both individual and envi-ronmental factors influence peer victimization (Swearer & Espelage, 2004). Although we acknowl-edge the importance of environmental factors such as the family, school, peer, community, andcultural contexts, the objective of this study was to identify individual factors (i.e., anxious-shybehaviors, social skills, and oppositional behaviors) that predict peer victimization in children withADHD.

Anxiety and social withdrawal are correlates of victimization by peers (Boivin et al., 1995;Hodges & Perry, 1999; Swearer, Grills, Haye, & Tam Cary, 2004). There is some controversyas to whether children who are anxious and socially withdrawn are more likely to be victimized

1 Hoza et al. (1993) defined the positive illusory bias as the propensity of children with ADHD to overinflate theirreports of their competencies in comparison with parent or teacher reports, or with their performance on an academicor social task.



because of the bully’s perception that they are weaker, or whether being bullied leads to anxietyand social withdrawal. In a longitudinal study, however, Hodges and Perry found that internalizingsymptoms contributed to increased victimization over time and that initial victimization predictedincreases in internalizing symptoms. The findings of this longitudinal study suggest that anxiety andsocial withdrawal are both risk factors for chronic victimization by peers and a consequence of it.Investigation of these risk factors was warranted, given the high levels of anxiety found in childrenwith ADHD (Tannock, 2000).

Several studies have demonstrated that children who are victims have social skills deficits(Champion, Vernberg, & Shipman, 2003; Fox & Boulton, 2005, 2006a, 2006b). Victims oftendisplay behavioral vulnerability (i.e., they look scared and unhappy, stand in a way that looks likethey are weak), and are nonassertive (i.e., put up with other children being nasty to them). Somevictims also engage in provocative behaviors such as annoying other children and spoiling their games(Fox & Boulton, 2005). Similarly, Champion et al. found that adolescent victims had lower scoreson the Cooperation and Assertiveness scales of the self- and parent-report versions of the SocialSkills Rating System (SSRS; Gresham & Elliott, 1990) than did adolescents who were not victims.Stormont (2001) reviewed the extensive literature on social outcomes of children with ADHD thatshows deficits in social knowledge, social perspective taking, and social interaction. Shea and Wiener(2003) found that social skills deficits, emotional volatility, a lack of insight, and immaturity werenoted by parents and teachers of boys with ADHD as at times causing them to be victimized by theirpeers or exacerbating chronic victimization. Consequently, in this study we investigated whethersocial skills predict variance in victimization by peers over and above ADHD symptoms.

Children with ADHD have high levels of conduct problems, including oppositional and defiantbehavior and aggression (Barkley, 2006, p. 190), with more than 65% of clinic-referred samplesbeing noncompliant and verbally hostile toward others. Angold, Costello, and Erkanli’s (1999)meta-analysis showed that children with ADHD were highly likely to have comorbid oppositionaldefiant and conduct disorder. Because the link between antisocial behavior and oppositional andhyperactive-impulsive symptoms is well established (Thapar, van den Bree, Fowler, Langley, &Whittinger, 2006), this study investigated whether oppositional behaviors mediate the associationbetween ADHD symptoms and bullying.

Unnever and Cornell (2003) examined whether self-reports of taking stimulant medicationfor ADHD predicted peer victimization, and whether self-ratings of self-control mediated thatrelationship. They found a direct relationship between self-reported ADHD and self-reports of beingvictimized by peers. Although self-reports of ADHD predicted self-control ratings, self-control wasnot associated with self-reports of being victimized. The relationship between self-reports of ADHDand self-reported bullying was indirect, with self-reports of ADHD predicting self-control, which inturn predicted self-reported bullying.

The following hypotheses were tested in relation to identifying predictors of victimization: 4)Children’s anxious-shy behavior and social skills will account for a significant portion of the variancein self-reports of being victimized by peers over and above ADHD symptoms. 5) Children’s parent-rated oppositional behavior will mediate the relationship between ADHD symptoms and bullying.Thus, when oppositional behavior is entered into a regression equation, the association betweenADHD symptoms and bullying will no longer remain significant.

METHOD

Participants

The participants were 104 9- to 14-year-old children; 52 (40 boys, 12 girls) were classifiedas having ADHD, and 52 (40 boys, 12 girls) were a typically functioning comparison group.



Table 1Demographic Information for Children with ADHD and Comparison Children

ADHD Comparison

Demographic Variable Mean (SD) Mean (SD) t(df = 102) p

Age in Months 137 (19.2) 140 (19.1) −.120 .25WIAT standard scores

Reading composite 102.04 (13.4) 111.69 (10.2) −4.10 <.001Writing composite 94.29 (14.61) 108.53 (14.1) −4.96 <.001Math composite 94.74 (14.25) 108.65 (14.2) −4.91 <.001IQ 104.62 (11.1) 113.02 (10.9) −.389 <.001

CPRS T-scoresInattentive 74.67 (9.55) 47.53 (6.68) 16.75 <.001Hyperactive-Impulsive 76.29 (10.35) 49.63 (6.94) 15.38 <.001ADHD total 77.42 (8.58) 48.45 (6.62) 19.22 <.001Oppositional 67.40 (12.49) 47.57 (5.95) 10.26 <.001Anxious-Shy 59.92 (14.21) 50.37 (9.0) 4.08 <.001

Notes. ADHD: Attention-Deficit/Hyperactivity Disorder, SD: standard deviation, WIAT: Wechsler Indi-vidual Achievement Test, CPRS: Conners’ Parent Rating Scale-Revised, Long Form.

Participants were required to have a full-scale IQ ≥ 80 on the Wechsler Intelligence Scale for Children– Third Edition (WISC-III; Wechsler, 1986) or the Wechsler Abbreviated Scale of Intelligence(WASI; Wechsler, 1999). As shown in Table 1, children with ADHD had a lower IQ score, loweracademic achievement scores on the Wechsler Individual Achievement Test (WIAT), and higherscores on the Diagnostic & Statistical Manual for Mental Disorders, Fourth Edition (DSM-IV)ADHD and Oppositional and Anxious-Shy subscales of the Conners’ Parent Rating Scales-Revised,Long Form (CPRS; Conners, 1997) than did children without ADHD. Children with and withoutADHD did not differ in age in months, the parent filling out questionnaires (Mother: ADHD = 90.4%;Comparison = 88.5%) chi-square (1, N = 104) = 2.20, p = .34, language other than English spokenat home (ADHD = 13.5%; Comparison = 17.3%) chi-square (1, N = 104) = 2.40, p = .30, or parenthighest education level chi-square (1, N = 104) = 9.70, p = .09.

Participants with ADHD were required to have received a previous diagnosis of ADHD accord-ing to DSM-IV criteria. To ensure that symptoms of ADHD were ongoing, the children’s parents andteachers completed the CPRS and the Conners’ Teacher Rating Scale-Revised, Long Form (CTRS;Conners, 1997), respectively. To be classified as having ADHD, children were required to be ratedin the Clinical range (T ≥ 70) on at least one of the core ADHD indexes (i.e., DSM-IV hyperactiveimpulsive, DSM-IV inattentive, and DSM-IV total) by their parent or teacher and to be rated in theBorderline or Clinical range (T ≥ 60) on at least one of the core ADHD indexes by the informantin the other setting. Children in the comparison group were rated on the CPRS to ensure that theydid not have symptoms of ADHD, and were excluded if they had a T score ≥ 60 on any of the coreADHD indexes or had any learning or behavior problems identified by their parent in response to aquestion asked at intake. Participants were also excluded if they had a diagnosis of a neurologicaldisorder or genetic syndrome (e.g., Autism Spectrum Disorder, Bipolar Disorder, or Tourette’s Dis-order) or if they were taking medication for their disorder other than a psychostimulant, accordingto parent report.

At the time of testing, 36 children with ADHD regularly took psychostimulant medication.Fifteen children with ADHD had previous comorbid diagnoses (learning disability: n = 11; op-positional defiant disorder: n= 4), and 20 (38.5%) scored in the Clinical range (T ≥ 70) on the



Oppositional scale of the CPRS. None of the children in the comparison group had been diagnosedwith any learning or behavior problems or had scores in the clinical range on the Oppositional scaleof the CPRS. Furthermore, 19 of the children with ADHD received special education in a resourceroom, and 2 were in contained special education classrooms. None of the children without ADHDreceived special education services.

Measures

Two measures were used to assess peer victimization. The Bully/Victim Questionnaire (BVQ),adapted by Boer-Hersh (2002) from Craig (1998) and based on a survey developed by Olweus (1991,1993), is a self-report measure consisting of 14 items with Likert scales that examine children’sexperiences of peer victimization at school. Prior to completing the questionnaire, children weregiven a definition of bullying. The questionnaire comprises four items that measure frequency ofpeer victimization (How often have you been bullied/ taken part in bullying since the beginning ofthe school year? About how many times have you been bullied/ taken part in bullying in the last fivedays of school?), two items about the duration of victimization (How long have you been bullied/taken part in bullying other kids?), and eight items about the type of victimization (verbal: Howoften do other students say mean and nasty things to you/Have you teased other kids and calledthem names?; physical: How often do other students try to push, kick, or hurt you/Have you triedto hit, push, or kick someone?; relational: How often has someone left you out of an activity onpurpose to hurt your feelings/Have you left someone out of an activity on purpose to hurt theirfeelings? and How often has someone spread nasty rumors about you to hurt your feelings/Haveyou spread nasty rumors about someone to hurt their feelings?). Boer-Hersh (2002) examined theconstruct validity and internal consistency of the BVQ. Exploratory factor analysis revealed twofactors accounting for 47.9% of the variance. The Victim scale (Cronbach’s alpha = .83), composedof the seven items assessing victimization, accounted for 25.73% of the variance (eigenvalue = 4.4).Factor loadings of the items on this scale ranged from 0.58 to 0.81. The Bully scale (Cronbach’salpha = .76), composed of the seven items assessing bullying, accounted for 22.18% of the variance(eigenvalue = 2.3). Factor loadings on this scale ranged from 0.43 to 0.83.

Because some children may be reluctant to report their own bullying behavior (Pellegrini, 2001;Pellegrini & Bartini, 2000), one item (How often does the child bully or threaten others?) from theparent and teacher forms of the SSRS (Gresham & Elliott, 1990) was used in addition to self-reports. The item was measured on a three-point scale, with 0 being “Never,” 1 being “Sometimes,”and 2 being “Often.” When both parents participated in the study, only the mother’s data wereanalyzed.

Children were classified as victims if they obtained a high total raw score ( ≥ 17) on theVictim scale of the BVQ, and as bullies if they obtained a high total raw score ( ≥ 17) on the Bullyscale of the BVQ. This cutoff score was considered high based on Kumpulainen et al.’s (1998)procedure whereby children who reported being victimized/bullying more than once or twice aweek were considered victims/bullies. Because the BVQ asked questions about specific types ofpeer victimization, a score of 17 would indicate that a child had either experienced or perpetrated allforms (relational, verbal, physical) of victimization at least once since the beginning of the schoolyear in addition to experiencing or perpetrating at least one form of victimization several timesa week, or that the child had engaged in or experienced more than one form of victimization orbullying several times a week. Children were also classified as bullies even if they did not attainthe cutoff score on the bullying scale of the BVQ if their parent or teacher indicated that they oftenbullied other children, or if their parent and teacher both indicated that they sometimes bulliedother children. Children were classified as bully/victims if they met criteria for both bullies and



victims. Thus, on the basis of the BVQ and the parent and teacher ratings of bullying, participantswere divided into four groups: victims (children who were victimized but were not bullies); bullies(children who bullied others but were not victimized themselves); bully/victims (children who bothbullied and were victimized); none (children who were neither victims nor bullies).

Two instruments were used to examine predictors of peer victimization. The CPRS (Conners,1997), a widely used rating scale with well-established reliability and validity, was administeredto parents of children with and without ADHD. When both parents participated in the study, onlythe mother’s data were analyzed. The CPRS has 80 items, 14 subscales, of which five were usedin this study: DSM-IV ADHD Total (test–retest reliability r = .76), DSM-IV Inattentive (test–retestreliability r = .67), DSM-IV Hyperactive-Impulsive (test–retest reliability r = .81), Anxious-Shy(test–retest reliability r = .47), and Oppositional (test–retest reliability r = .57). For children whowere 9–14 years of age, the internal consistency coefficients ranged from .81 to .95.

The SSRS Parent and Teacher Forms (Gresham & Elliott, 1990) were used to assess the socialskills of the children. The Total Social Skills standard scores were used in the analyses. Both scaleshave two forms, one for Grades K–6, and one for Grades 7–12. The Total Social Skills scales on allfour forms have high internal consistency and test–retest reliability (Parent: Cronbach’s alpha = .87–.90, test–retest reliability r = .77–.84; Teacher: Cronbach’s alpha = .93–.94, test–retest reliabilityr = .75–.88).

Procedure

This study was approved by the Research Ethics Boards of the University of Toronto, Hospitalfor Sick Children, and The Scarborough Hospital, all in Toronto, Canada. Parents of childrendiagnosed with ADHD recruited from the participating hospital clinics were sent information aboutthe study and were invited to participate. Others were referred by physicians and psychologists inthe community or responded to advertisements in newsletters of associations serving children withADHD. Parents of children in the comparison group responded to advertisements in public placessuch as community centers, libraries, bookstores, and community-based newspapers.

Two research assistants worked with each family, one with the children and one with the parents.Testing took approximately 4 hours for children with ADHD and 3 hours for comparison children.During this time, the children were given the WASI (if recent IQ data were not available), the WIAT,and the BVQ, as well as several measures for other studies. The children were given copies of theBVQ, the research assistant read the items aloud to them, and the children circled their desiredresponses on the written copy. Parents completed demographic questionnaires, the CPRS and theSSRS (Gresham & Elliott, 1990), along with several measures for other studies. Teachers weremailed a package including the SSRS and the CTRS to be completed and returned in the envelopeprovided.

RESULTS


The first set of analyses investigated whether children with ADHD differed from comparisonchildren in frequency of peer victimization (hypotheses 1 and 2) and whether these differences wereaffected by gender. Three two-way analyses of variance (ANOVA) were performed with ADHD status(ADHD vs. comparison) and gender as the between-subject factors. Self-reported victimization andself-reported bullying on the BVQ, and a composite of the parent- and teacher-reported responsesto the question “How often does the child bully or threaten others?” were the dependent variables.As shown in Table 2, children with ADHD reported higher levels of being victimized by peers thandid comparison children. Although the gender effect was not significant, there was a significant



Table 2Self-Reported Victimization and Bullying Total Scores by ADHD Status and Gender

ADHD Comparison

Mean SD Mean SD F (1, 103) p η2

VictimizationVictimization (BVQ) 13.65 5.41 9.92 2.78 24.37a .001 .197Male 13.10 5.28 10.35 2.86 .078b .781 .001Female 15.50 5.65 8.50 1.98 4.63c .034 .044Verbal 2.62 1.40 1.81 1.01Physical 1.65 .93 1.33 .62Relational 1.68 .75 1.34 .51

BullyingBullying (BVQ) 9.85 3.71 8.88 2.83 .813a .369 .008Male 10.32 3.98 9.13 2.95 4.23b .042 .041Female 8.25 2.01 8.08 2.27 .465c .497 .005Parent-Teacher .865 .97 .192 .445 10.67a .001 .096Male 1.03 1.03 .25 .494 7.70b .007 .072Female .333 .492 0 0 1.69c .196 .017

aAttention-Deficit/Hyperactivity Disorder (ADHD) status main effect. bGender main effect. cADHDstatus × Gender interaction.

Note. Victimization (Bully/Victim Questionnaire; BVQ) and Bullying (BVQ) are total raw scores.Parent-Teacher is the composite score for the item “How often does this child bully or threaten others?”on the Social Skills Rating System. SD: standard deviation.

ADHD status × Gender interaction; the differences in victimization by peers between children withand without ADHD were greater for girls than for boys. There were no ADHD status differencesin self-reported bullying. Boys, however, reported higher levels of bullying others than did girls.Parents and teachers reported that children with ADHD bullied and threatened others more oftenthan did children without ADHD, and boys bullied others more often than girls did. The ADHDstatus × Gender interactions were not significant for self-reported or parent- and/or teacher-ratedbullying.

A 2 × 3 profile analysis was done with ADHD status as the between-subjects factor and Typeof Victimization (Verbal, Physical, Relational) as the within-subjects factor (Table 2) to explorewhether children with and without ADHD report different frequencies of being subjected to verbal,physical, and relational victimization. According to Tabachnick and Fidell (2007), a profile analysisis an application of a multivariate ANOVA that is used to compare the profiles of two or moregroups of participants on several dependent variables with the same scaling administered at the samepoint in time. In accordance with the hypothesis, children with ADHD were subjected to all threetypes of victimization more frequently than were comparison children F (1,102) = 14.50, p = .05,Partial η2 = .12. The within-subjects effect was also significant F (1,102) = 33.68, p <.001, Partialη2 = .25. Pairwise comparisons showed that children were subjected to verbal victimization moreoften than relational (p < .001) and physical (p <.001) victimization. The Type of Victimization ×ADHD status interaction effect was not significant F (1,102) = 3.17, p = .08, Partial η2 = .03.

Hypothesis 3 proposed that when self-, parent-, and teacher-report data are pooled, children withADHD would be more likely than children without ADHD to be classified as victims, bullies, andbully/victims. The hypothesized differences in classification were significant: chi-square (3) = 22.67,p < .001. Of the children with ADHD, 26.9% (n = 14) were classified as victims, 17.3% (n = 9)as bullies, 13.5% (n= 7) as bully/victims, and 42.3% (n= 22) as neither victims nor bullies. Of



the children without ADHD, 3.9% (n = 2) were classified as victims, 5.8% (n= 3) as bullies, 3.9%(n= 2) as bully/victims, and 86.4% (n= 45) as neither victims nor bullies.


The first step in investigating the predictors of peer victimization proposed in hypotheses 4and 5 was to compute Pearson correlations between relevant variables to determine which variablesshould be used to measure each construct. Given the high correlations (p < .001) between theDSM-IV ADHD scales on the CPRS (Inattentive with Hyperactive-Impulsive r = .832; Inattentivewith ADHD Total r = .964; and Hyperactive-Impulsive with ADHD Total r = .941), the DSM-IVADHD Total T-score was used in the regression analyses described below. The total score on theVictim scale of the BVQ was used in the analyses predicting victimization by peers, and the totalscore on the Bully scale of the BVQ was used in the analyses predicting self-reported bullying.Because of the high correlation (r = .831, p < .001) between the parent and teacher items on theSSRS measuring bullying (i.e., Bullies or Threatens Others), a composite of the two scores wascreated and used in the analyses to measure parent- and teacher-reported bullying. The Anxious-ShyT-score of the CPRS was used as the measure of anxiety, the Total Social Skills standard scores onthe Parent and Teacher forms of the SSRS were used to measure social skills, and the OppositionalT-score of the CPRS was used as the measure of conduct problems.

Hypothesis 4 stated that anxious-shy behavior and social skills would predict variance invictimization by peers over and above ADHD symptoms. Total Victim score on the BVQ wascorrelated with all of the predictor variables, and ADHD symptoms was highly correlated withanxious-shy behavior and social skills (Table 3). A hierarchical regression analysis was conducted totest this hypothesis (Table 4). The ADHD–DSM-IV Total score was entered at step 1; CPRS Anxious-Shy and the Total Social Skills standard scores from the Teacher and Parent forms of the SSRS wereentered at step 2. ADHD–DSM-IV Total score predicted a significant portion of the variance in totalVictim score, R2 = .195, F (1.101) = 22.22, p < .001. The variables added at step 2 did not predictsignificant additional variance in the Total Victim score, R2 = .222,F (1.101) = 1.05, p = .373.

Hypothesis 5 predicted that oppositional behavior would mediate the association betweenADHD symptoms and bullying. As discussed by Baron and Kenny (1986), mediator models can

Table 3Pearson Correlations among Self-Reported Peer Victimization, Self-reported Bullying, Parent- and Teacher-Reported Bullying, Age, ADHD Symptoms, Oppositional Behaviors, Anxious-Shy Behaviors, and Social Skills

Variable 1 2 3 4 5 6 7 8 9

1. Victimization (BVQ) 1.02. Bullying SR (BVQ) .314∗∗ 1.03. Bullying PTR (SSRS) .067 .191 1.04. Age (months) −.128 .205∗ −.042 1.05. CPRS DSM-IV .419∗∗∗ .097 .341∗∗∗ −.038 1.0

Total ADHD6. CPRS Oppositional .307∗∗ .157 .549∗∗∗ −.063 .778∗∗∗ 1.07. CPRS Anxious-Shy .289∗∗ −.026 .087 .027 .466∗∗∗ .455∗∗∗ 1.08. Social Skills - Parent −.321∗∗ −.155 −.452∗∗∗ .074 −.702∗∗∗ −.731∗∗∗ −.390∗∗∗ 1.09. Social Skills Teacher −.111 −.025 −.222∗ .051 −.767∗∗∗ −.413∗∗∗ −.149 .443∗∗∗ 1.0

∗p <05. ∗∗p <.01. ∗∗∗p <.001.Notes. ADHD: Attention-Deficit/Hyperactivity Disorder, BVQ: Bully/Victim Questionnaire, SSRS: Social Skills Rating

System, CPRS: Conners’ Parent Rating Scale-Revised, Long Form, DMS-IV: Diagnostic & Statistical Manual of MentalDisorders, Fourth Edition, SR: self-reported, PTR: parent- and teacher-reported.



Table 4Hierarchical Linear Regression Analysis for Variables Predicting Self-Reported Peer Victimizationand Parent/Teacher-Reported Bullying (N = 104)

Variable B SE B β

Peer VictimizationStep 1

CPRS DSM-IV ADHD Total T-score .120 .026 .441∗∗∗

Step 2CPRS DSM-IV ADHD Total T-score .127 .042 .464∗∗

SSRS Teacher Social Skills Standard Score −.009 .032 −.038SSRS Parent Social Skills Standard Score .050 .036 .161CPRS Anxious-Shy T-score .030 .038 .085

Parent/Teacher Reported BullyingStep 1

CPRS DSM-IV ADHD Total T-score .017 .005 .337∗∗∗

Step 2CPRS DSM-IV ADHD Total T-score .001 .007 .013CPRS Oppositional T-score .025 .009 .417∗∗

∗p <.05. ∗∗ p <.01. ∗∗∗ p <.001.Notes. Peer Victimization: R2 = .195 for Step 1; �R2 = .028 for Step 2; Parent/Teacher-Reported Bullying

R2 = .114 for Step 1; �R2 = .068 for Step 2. SE: standard error, ADHD: Attention-Deficit/Hyperactivity Disorder,CPRS: Conners’ Parent Rating Scale-Revised, Long Form, DMS-IV: Diagnostic & Statistical Manual of MentalDisorders, Fourth Edition,

only be computed when the dependent variable is correlated with each of the predictors, and thepredictors are correlated with each other. Because the correlations between self-reported bullyingon the BVQ and the predictor variables were not significant, it was not possible to test a mediatormodel for this dependent variable. Parent/Teacher-reported bullying, however, was significantlycorrelated with the ADHD–DSM-IV Total and Oppositional scales on the CPRS, and the latter twovariables were correlated with each other. A hierarchical regression analysis was conducted to testthe mediating model, with Parent/Teacher-reported bullying as the dependent variable (Table 4).The ADHD–DSM-IV Total score was entered at step 1, and CPRS Oppositional T-score at step 2.The ADHD–DSM-IV Total score predicted a significant portion of the variance in Parent/Teacher-reported bullying before the CPRS Oppositional T-score was added, R2 = .114,F (1,100) = 12.81,p = .001. When CPRS Oppositional T-score was added to the model, additional variance waspredicted (R2 = .182, F (1,99) = 8.27, p = .005) and the association between ADHD symptoms andbullying was no longer significant. Thus, oppositional behavior mediated the association betweenADHD symptoms and bullying.

DISCUSSION


This study investigated peer victimization in a sample of children diagnosed with ADHD. Thefirst objective was to establish whether children with ADHD are victimized by peers and bullyothers more frequently than comparison children. The results showed that children with ADHDwere more likely than comparison children to report being victimized by peers and that this wasespecially problematic for girls with ADHD. Children with ADHD also reported that they weresubjected to verbal, physical, and relational victimization more often than their counterparts withoutADHD. Although children with ADHD were no more likely than comparison children to report that



they bullied others, their parents and teachers reported that they bullied and threatened others morefrequently. All sources indicated that boys bullied others more frequently than girls. Children withADHD were more likely to be classified as victims, bullies, and bully/victims than were childrenwithout ADHD.

Extensive research has shown that children with ADHD are at risk for rejection by peers (e.g.,Bagwell et al., 2001; Gresham & MacMillan, 1997; Hinshaw, 2002). The results of the presentstudy showed that their peer relationship problems go beyond being disliked. When data fromparent, teacher, and self-reports were pooled, 57.7% of these 9- to 14-year-old children experiencedproblems with being victimized, bullying others, or both, compared to 13.6% in the comparisongroup. This extraordinarily high rate of peer victimization should make this issue a focus of bothresearch and intervention with children with ADHD.

This study expanded on the Unnever and Cornell (2003) study in several ways. In the presentstudy, the children had received a diagnosis of ADHD by a physician or psychologist at least 1 yearprior to data collection, and rigorous cutoffs on the Conners Rating Scales (Conners, 1997) wereused to ensure that their symptoms were ongoing. This addressed a key limitation of the Unnever andCornell study, in which children with ADHD were identified by their self-reports of taking stimulantmedication.

The BVQ is a well-established self-report measure of peer victimization. Because self-report hasbeen found to be more sensitive than parent and teacher reports for assessing victimization by peers(e.g., Juvonen et al., 2001; Pellegrini, 2001), the absence of parent and teacher ratings of victimizationin the Unnever and Cornell (2003) study and the present study is not a significant limitation. Bothstudies showed that children with ADHD reported being victimized more frequently than comparisonchildren. In the present study, we included parent and teacher ratings of bullying and threateningothers in addition to self-reports of bullying. There were informant differences, with self-reportsshowing no differences between children with and without ADHD, and parent and teacher ratingsindicating that children with ADHD bullied and threatened others more often. Interpretation of thisfinding is difficult. On the one hand, there is considerable evidence that bullies tend to underreporttheir bullying behaviors, requiring assessment from other sources (e.g., Pellegrini, 2001) and thataggressive boys tend to underreport their own aggressive behavior, whereas nonaggressive boystended to overestimate their own aggressiveness (Lochman, 1987), and that children with ADHDhave a positive illusory bias leading them to overinflate reports of their competencies in academicand social domains (e.g., Hoza et al., 1993, 2002). Thus, children with ADHD may lack insight intotheir own behavior, and may not define their negative behavior toward peers as bullying. However,the conclusion that our parent and teacher measure, a single item on the SSRS, was more credibleshould be adopted cautiously. Respondents were not given a definition of bullying prior to completingthe SSRS, and may therefore have based their ratings on frequency of aggressive behavior withoutconsidering whether there was a power imbalance between the bully and the victim. They may alsonot have considered relational bullying when they answered this question. Furthermore, childrenwith ADHD may be viewed by teachers and parents as bullies when their aggression is reactive; inother words, they react aggressively in response to being victimized (Shea & Wiener, 2003).

Children with ADHD had higher frequencies of self-reports of being subjected to verbal,relational, and physical victimization. Verbal victimization was the most frequent, and relationaland physical victimization were lower and roughly comparable. This pattern was the same forboth groups. Shea and Wiener (2003), however, found that relational victimization was extremelyupsetting for children with ADHD. Although verbal victimization occurs more frequently, relationalvictimization in the form of social exclusion and isolation may be perceived as more salient anddistressing. Thus, children with ADHD would be more likely to emphasize relational victimizationin an unstructured interview but not on a questionnaire.



The higher frequency of self-reports of being victimized by peers in children with ADHD ismore pronounced in girls. This is consistent with previous research indicating that girls with ADHDare more likely to be rejected by peers and to have social problems than are boys with ADHD (Arnold,1996; Berry et al., 1985; Rucklidge & Tannock, 2001). The finding that boys reported higher levelsthan did girls of bullying others is consistent with the literature but should be interpreted with cautionbecause reporting aggressive behavior may be less socially undesirable for girls than for boys, andparents and teachers may have focused on physical aggression as opposed to relational aggression(Espelage et al., 2004).


The second objective of the study was to examine predictors of peer victimization. Parent ratingsof anxious-shy behaviors and parent and teacher ratings of social skills were correlated with childreports of being victimized. These variables, however, did not predict the Total Victim score over andabove parent ratings of ADHD symptoms. Similar to Unnever and Cornell (2003), the relationshipbetween ADHD symptoms and self-reported victimization by peers was direct, suggesting thatanxious-shy behavior and social skills predicted victimization because they shared variance withADHD symptoms. Furthermore, the anxious-shy scale on the CPRS and the Social Skills scaleson the SSRS may not adequately measure the specific aspects of anxiety, social withdrawal, andsocial skills that are most closely associated with peer victimization (i.e., behavioral vulnerabilityand being nonassertive) (Fox & Boulton, 2005).

The hypothesis that parent-rated oppositional behavior would mediate the association betweenADHD symptoms and bullying others was partially supported. Self-reported bullying was notcorrelated with either parent-rated ADHD symptoms or oppositional behavior. Parent ratings of op-positional behavior, however, mediated the association between parent-rated ADHD symptoms andparent and teacher ratings of the frequency that children bullied or threatened others. Although theOppositional scale of the CPRS does not have any items that explicitly measure bullying, many ofthe items describe characteristics of bullies found in other studies, such as being angry and resentful,fighting, being defiant, blaming others, and losing their temper (Coolidge et al., 2002; Salmon et al.,2000). Therefore, it was not surprising that parent-rated oppositional behavior was correlated withParent/Teacher-reported bullying. Of more importance, however, is the finding that the associationbetween ADHD symptoms and Parent/Teacher-reported bullying became nonsignificant when Op-positional behavior was entered into the equation. Furthermore, many of the oppositional behaviorson the CPRS occur when a child loses control. In that sense, the indirect relationship between ADHDand bullying is similar to that found by Unnever and Cornell (2003).

Limitations of the Present Study

This study has some limitations. All but five of the children with ADHD had clinical orborderline scores on both the ADHD Inattentive and Hyperactive-Impulsive scales of the CPRS orCTRS. Therefore, the variables studied could not be broken down by ADHD subtype. This findingis important because children who have been diagnosed with ADHD–Inattentive Type are moresocially withdrawn and less aggressive than children diagnosed with ADHD–Combined Type orADHD–Hyperactive-Impulsive Type (Blachman & Hinshaw, 2002; Hodgens, Cole, & Boldizar,2000). Therefore, children with ADHD–Inattentive Type might be more likely to be victimized, andthose with Hyperactive-Impulsive and Combined Types might be more likely to bully others.

The children with ADHD in this study all had ongoing symptoms within the clinical range.Although children with below average intellectual ability, bipolar disorder, autism spectrum disor-ders, and Tourette’s disorder were not included in the sample, children with high levels of dysphoria,



anxiety, oppositional behaviors, conduct problems, and learning disabilities were included. Thus,the children with ADHD in this study were not a pure sample, and many had comorbid disorders.Although this might be seen as a limitation of the study, inclusion of these children makes the samplemore ecologically valid in that it better reflects children with ADHD in the community (Barkley,2006, p. 184). For example, in an epidemiological study with a large community sample conductedin Ontario, Canada (the location of the present study), 44% of children with ADHD had at least oneother psychiatric disorder, 32% had two disorders, and 11% had three or more disorders (Szatmari,Boyle, & Offord, 1989).

In the present study, measurement of bullying was problematic because the parent and teachermeasure had only one item, and children with ADHD tend to have a positive illusory bias in reportingtheir competencies in the social domain (Hoza et al., 1993, 2002). Furthermore, administering theBVQ to children in a one-on-one situation and reading it aloud to them may have discouraged themfrom reporting their bullying behavior honestly. Moreover, measures of peer victimization typicallyassess frequency of aggressive behaviors, but do not reliably assess the power differential betweenbully and victim and the intent of the bully to hurt the victim.

Implications for School Psychologists

Understanding that children with ADHD appear to be at high risk for peer victimization hasimportant implications for school psychologists. First, assessments of children with ADHD shouldinclude a thorough investigation of their peer relationships including peer acceptance, friendships,and peer victimization because their problematic peer relationships can have a profound impacton their emotional well-being (Shea & Wiener, 2003). Second, verbal victimization is much morefrequent than physical victimization in schools, possibly due to zero-tolerance policies for physicalaggression (Craig & Pepler, 2007; Shea & Wiener, 2003). More information should be providedto teachers about the forms bullying can take and about the fact that children with ADHD, inaddition to bullying others, are at significant risk for being victimized by their peers. Third, cur-rent pharmacological and psychosocial interventions that result in reduction of negative behaviorin children with ADHD typically do not have a substantial impact on peer relationships (Hozaet al., 2005). A developmental-systemic approach designed to prevent peer victimization in schoolmay enhance outcome in this respect (Pepler, 2006). Children with ADHD and other at-risk childrenshould be provided with scaffolding to develop social problem-solving and anger management skills,and reduce ADHD behaviors that are annoying to other children, using empirically supported socialskills training programs such as S.S. Grin (DeRosier, 2004; DeRosier & Marcus, 2005). Primaryprevention approaches that change the social dynamics of the school such as teacher education andpeer conflict–mediation programs (e.g., Cunningham et al., 1998) should also be offered.

ACKNOWLEDGEMENT

This study was funded by a grant from the Social Sciences and Humanities Research Councilof Canada.

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